String order and registers
A guzheng has 21 strings, numbered from string 21 (thickest, lowest) up to string 1 (thinnest, highest). In D tuning, string 21 is D2 and string 1 is D6, repeating the pentatonic scale (D-E-F sharp-A-B) across four octaves plus one note.
The low register (strings 21-15) has thick strings and long sustain, so it is the easiest to detect. The high register (strings 5-1) decays quickly, so pluck a few times for a stable reading.
Guzheng tunings
| 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 21-string D tuning | D2 | E2 | F♯2 | A2 | B2 | D3 | E3 | F♯3 | A3 | B3 | D4 | E4 | F♯4 | A4 | B4 | D5 | E5 | F♯5 | A5 | B5 | D6 |
| 21-string G tuning | D2 | E2 | G2 | A2 | B2 | D3 | E3 | G3 | A3 | B3 | D4 | E4 | G4 | A4 | B4 | D5 | E5 | G5 | A5 | B5 | D6 |
| 21-string C tuning | D2 | E2 | G2 | A2 | C3 | D3 | E3 | G3 | A3 | C4 | D4 | E4 | G4 | A4 | C5 | D5 | E5 | G5 | A5 | C6 | D6 |
Tuning order and technique
Work from the low register upward. With so many strings under high tension, adjusting one moves the bridges and soundboard and slightly shifts its neighbours, so give the whole instrument a second pass when you finish.
Turn the tuning wrench slowly while plucking: a needle to the left means flat (raise it), to the right means sharp (lower it). Picks give a clearer tone than fingers; keep the plucking point consistent, just right of the bridge.
If a string refuses to settle, check whether its bridge has shifted or is pinching the string before replacing the string.
Getting to G and C tuning
Guzheng players change key by moving the bridges, not by transposing everything. Raise the 3rd degree (mi) of the D pentatonic scale - strings 4, 9, 14 and 19 - by a semitone by sliding those bridges toward the front nut. That note becomes the new tonic (do) and you are in G.
From G, raise the 3rd degree again on strings 2, 7, 12 and 17 by a semitone and you reach C.
Different schools and pieces use other tunings; follow your teacher or the score when it specifies one.
